North Korea has unveiled the embalmed body of Kim Jong Il, still in his trademark khaki jumpsuit, on the anniversary of his death as mourning mixed with pride over a recent satellite launch that was a long-held goal of the late authoritarian leader.

Kim lies in state a few floors below his father, national founder Kim Il Sung, in the Kumsusan mausoleum, the cavernous former presidential palace.

Kim Jong Il is presented lying beneath a red blanket, a spotlight shining on his face in a room suffused in red.

Wails echoed through the chilly hall as a group of North Korean women sobbed into the sashes of their traditional Korean dresses as they bowed before his body.

The hall bearing the glass coffin was opened to select visitors for the first time since his death.

North Korea also unveiled Kim's yacht and his armoured train carriage, where he is said to have died.

Among the personal belongings featured in the mausoleum are the parka, sunglasses and pointy platform shoes he famously wore in the last decades of his life. A MacBook Pro lay open on his desk.

Cameras were not allowed inside the mausoleum, and state media did not release any images of Kim Jong Il's body.

ONE YEAR ON

The elder Kim died on December 17, 2011, from a heart attack while travelling on his train.

His death was followed by scenes of North Koreans dramatically wailing in the streets of Pyongyang, and of the 20-something son leading ranks of uniformed and gray-haired officials through funeral and mourning rites.

The mood in the capital was decidedly more upbeat a year later, with some of the euphoria carrying over from last week's launch of a long-range rocket that sent a satellite named after him to space.

The launch, condemned in many other capitals as a violation of bans against developing its missile technology, was portrayed not only as a gift to Kim Jong Il but also as proof that his young son, Kim Jong Un, has the strength and vision to lead the country.

The satellite bears one of Kim Jong Il's nicknames, Kwangmyongsong, or "Lode Star," a moniker given to him at birth according to the official lore.

To honour him, North Koreans stopped in their tracks at midday and bowed their heads as the national flag fluttered at half-staff along streets and from buildings.

Pyongyang construction workers took off their yellow hard hats and bowed at the waist as sirens wailed across the city for three minutes.

Tens of thousands of North Koreans gathered in the frigid plaza outside, newly transformed into a public park with lawns and pergolas.

"Just when we were thinking how best to uphold our general, he passed away," Kim Jong Ran said at the plaza.

"But we upheld leader Kim Jong Un. ... We regained our strength and we are filled with determination to work harder for our country."

Speaking outside the mausoleum, renamed the Kumsusan Palace of the Sun, the military's top political officer, Choe Ryong Hae, said North Korea should be proud of the satellite, calling it "a political event with great significance in the history of Korea and humanity."